Vice systems and clamping systems are well known, including one or more movable jaws which are positioned to secure a workpiece in place. Workpieces may be held between movable jaws and fixed jaws, or just between movable jaws. Vises are frequently carried by pallets which are shuttled into the appropriate position for machining. In such applications, while parts on one pallet are being machined, finished parts can be unloaded and unfinished parts loaded on vises carried by other pallets.
Most prior art vises utilize a mechanically driven mechanism, such as a screw, either alone or in conjunction with hydraulic actuation. In use, the mechanical mechanism advances the one or more movable jaws to a position proximal to the workpiece. For a mechanical system, the mechanical mechanism provides the entire clamping force, whereas in a combination system, the jaws are hydraulically advanced the last portion of their stroke to contact and secure the workpiece in place.
Mechanical systems increase the time required to load parts and are difficult to automate economically. Obtaining accurate and repeatable clamping forces and accurate positioning with mechanical systems can be difficult. While combination mechanical/hydraulic systems can be better than purely mechanical systems, they still suffer many of the same drawbacks.
Additionally, significant impacts can be exerted on the part by the cutting tool, giving rise to the possibility that the workpiece may shift, causing reject parts, or allow the part to be “caught” by the cutting tool and ripped out of the vise. It is possible for a caught part to be forcefully thrown from the vise and cause injury. If aluminum or other soft material top jaws are used, impacts delivered to the workpiece and transmitted to the jaws can result in deforming the jaws and allowing the part to become loose. To overcome this, mechanical vises have to be mechanically adjusted, such as by the operator, to take up the slack. A hydraulic vise can take up the slack, making the use of aluminum jaws much safer.
There is a need in the art for a vise which is fully hydraulic, which allows the operation of the vise to be automated.